CN101442958B - Apparatus for cardiac valve replacement - Google Patents

Abstract

A method of placing a valve within a tubular organ, the method comprising delivering an expandable tubular adapter to a desired location within the tubular organ, wherein the adapter includes an enclosed volume surrounded by an outer wall spaced from an inner wall, and a first end wall and a second end wall. The method also includes expanding the outer wall relative to the inner wall such that the outer wall contacts the tubular organ and positioning the valve within the inner wall of the adapter. The method also includes placing a material within the enclosed volume of the adapter to expand the outer wall relative to the inner wall, where the material may include a liquid or a gel. Alternatively, the valve may be placed within the inner wall prior to delivery of the adapter to the desired site.

Description

Heart Valve Replacement Devices

technical field

The present invention relates generally to the treatment of heart valve disease and, more particularly, to the replacement of malfunctioning pulmonary valves.

Background technique

In recent years, there has been increasing focus on minimally invasive and percutaneous replacement of heart valves. In the specific case of pulmonary valve replacement, U.S. Patent Application Publication Nos. 2003/0199971 A1 and 2003/0199963 A1, filed by Tower et al. and incorporated herein by reference in their entirety, describe A valved bovine jugular vein segment used as a replacement for the pulmonary valve. The replacement valve is mounted in a balloon catheter and delivered percutaneously through the vasculature to the site of the aberrant pulmonary valve, where it is expanded by the balloon to compress the native valve leaflets against the right ventricular outflow tract, anchoring and sealing the replacement valve. Such as the paper "Percutaneous Insertion of the Pulmonary Valve", Bonhoeffer et al., "Journal of the American College of Cardiology" (Journal of the American College of Cardiology) 2002; 39: 1664-1669 and "Bovine Transcatheter Replacement of a Bovine Valve in Pulmonary Position, Bonhoeffer et al., Circulation 2000;102:813-816, which is hereby incorporated by reference in its entirety, Implantable Pulmonary valve replacement to replace a native or prosthetic pulmonary valve within a valved catheter. Other papers that characterize percutaneous valve implantation include Louise Coats et al., The Potential Impact of Percutaneous Pulmonary Valve Stent Implantation on Right Ventricular Outflow Tract Re-Intervention ), "European Journal of Cardio-Thoracic Surgery (England)", April 2005, pp. 536-43; Peter C. Block et al. "Percutaneous approach to heart valve disease Percutaneous Approaches to Valvular Heard Disease, Current Cardiology Reports (United States), March 2005, pp. 108-13; Georg Lutter et al. Percutaneous Valve Replacement: Latest Percutaneous Valve Replacement: Current State and Future Prospects, Annals of Thoracic Surgery (Netherlands), December 2004, pp. 2199-206; Younes Boudjemline et al. Percutaneous Pulmonary Valve Replacement in a Large Right Ventricular Outflow Tract: An Experimental Study, Journal of the American College of Cardiology (USA) of Cardiology (United States)), March 17, 2004, pp. 1082-7; S. Khambadkone et al., Percutaneous Implantation of Pulmonary Valyes, Expert Review of Cardiovascular Therapy ( UK) (Expert Review of Cardiovascular Therapy (England)), November 2003, No. 5 pp. 41-18; Y. Boudjemline et al., Percutaneous Valve Insertion: A New Approach, Journal of Thoracic and Cardiovascular Surgery (USA). CardiovascularSurgery (United States)), March 2003, pp. 741-2; Philipp Bonhoeffer et al, "Percutaneous Insertion of the PulmonaryValye", Journal of the American College of Cardiology (USA) (Journal of the American College of Cardiology (United States)), May 15, 2002, pp. 1664-9; YounesBoudjemline et al., Steps Toward Percutaneous Aortic Valve Replacement, Circulation (United States)" (Circulation (United States)), February 12, 2002, pp. 775-8; P. Bonhoeffer et al., "Percutaneous Replacement of Pulmonary Valve in Right Ventricular to Pulmonary Artery Catheters with Valve Dysfunction" (Percutaneous Replacement of Pulmonary Valve in a Right-Ventricle to Pulmonary-Artery Prosthetic Conduit with Valve Dysfunction), "The Lancet (UK)" (Lancet (England)), October 21, 2000, pp. 1403-5; P. Bonhoeffer et al., Transcatheter Implantation of a Bovine Valve in Pulmonary Position: A Lamb Study, Circulation (United States), 15 Aug. 2000 pp. 813-6; G.O. Yonga et al., Effect of Percutaneous Balloon Mitral Valvotomy on Pulmonary Venous Flow in Severe Mitral Stenosis, East African Medical Journal (Kenya), January 1999, pp. 28-30; and G.O. Yonga et al., Percutaneous Endoluminal Balloons for Pulmonary Valve Stenosis Percutaneous Transluminal Balloon Valvuloplasty for Pulmonary ValveStenosis: Report on Six Cases, East African Medical Journal (Kenya), April 1994, pp. 232- 5 pages, the entirety of which is hereby incorporated by reference.

Although the pulmonary valve replacement approach described in the aforementioned patent application and paper appears to be a viable treatment, not all available valved bovine jugular vein segments are available in a relatively narrow size range, typically down to a diameter of approximately 22 mm. Available to all beneficiaries. Unfortunately, the most common patient population requiring pulmonary valve replacement is adults and children who have received a transannular patch repair of tetralogy of Fallot as infants, causing their right ventricle to outflow The diameter of the track is greater than 22mm. Therefore, conventional vein segments generally cannot be safely implanted in these patients.

Figure 1 shows an example of a prior art adapter stent 10 that has been developed to allow a valved bovine jugular segment to be used in a patient with a large right ventricular outflow tract. Stent 10 comprises a wire mesh scaffold made of Nitinol wire that has been heat treated by conventional techniques to memorize its configuration as shown. In the example shown, the adapter stent 10 is substantially a cylindrical wire structure defining a lumen. Adapter stent 10 generally has a cylindrical proximal portion 12 and a distal portion 14 each having a diameter large enough to contact the interior of the outflow tract into which it will be implanted. The proximal portion 12 and the distal portion 14 taper toward a substantially cylindrical central portion 16 of reduced diameter in which a valved vein segment or other replacement valve may be installed.

FIG. 2 is an end view of the adapter stent 10 shown in FIG. 1 including a valved vein segment 18 having a plurality of leaflets 20 . The vein segment 18 is sutured to the adapter stent 10 along the proximal and distal edges of the stent, and may also be sutured to the stent to the greatest extent, if not covering all of the stent wire intersections of the vein segment. Additional sutures have been described for the area between the valve commissures. An example of the assembly of suitable valve components is found in assignee's co-pending U.S. patent application, "Heart Apparatus for Treatment of Cardiac Valves and Method of Its Manufacture.

3 is a schematic cross-sectional view of a replacement valve of the type shown in FIG. 1 implanted in the right ventricular outflow tract 40 . As shown, the proximal portion 12 and the distal portion 14 of the adapter stent 10 are positioned such that the larger diameter portion contacts the inner wall of the outflow channel 40 . The adapter stent 10 can push away the native valve leaflets 42, which allows the leaflets 20 of the valved vein segment 18 to implant in the original position of the native valve. The location of the adapter stent 10 can also be such that the proximal segment compresses the native leaflet against the outflow tract wall or can also be positioned downstream of the native leaflet 42 .

However, there remains a need to provide a variety of devices to suit different patients, as well as to improve devices usable for implanting relatively smaller diameter valve segments in relatively larger diameter patient regions.

Contents of the invention

The present invention generally seeks to provide a mechanism that permits the use of a replacement valve at a location where the desired location of the replacement valve has a larger diameter than the available replacement valve. More specifically, the present invention seeks to provide a mechanism that allows a valved venous segment, such as the bovine jugular vein, to be used as a replacement pulmonary valve in patients with a large right ventricular outflow tract. However, the present invention may also be used in conjunction with other replacement valves such as those disclosed in US Pat. Nos. 6,719,789 and 5,480,424 to Cox or other valves comprising, for example, pericardial tissue, nitinol metal, and/or polymers. It is further contemplated that segments of porcine or equine veins may be used in conjunction with the devices of the present invention.

The present invention achieves the above objects by providing an expandable adapter stent configured to have a substantially cylindrical outer wall when expanded with a diameter large enough to engage and seal the inner vessel wall at the desired graft site. The adapter holder further includes an interior that is substantially cylindrical and has a diameter that is smaller than the diameter of the outer wall of the adapter holder. The inner wall extends along the length of the adapter stent and has an inner diameter substantially equal to the outer diameter of a valved vein segment or other replacement valve positioned or to be positioned therein.

In a first configuration of the invention, a valved vein segment or other replacement valve is positioned inside the adapter stent prior to implantation. In a second configuration, a valved vein segment or other replacement valve is placed within the interior of the adapter stent after the adapter stent is first implanted. In this embodiment, the replacement valve may itself fit within an expandable valve stent as described in the Tower et al. application and the Bonhoeffer et al. paper cited above. The stent used in the present invention may be a self-expanding stent type such as made of Nitinol metal or may be a stent expandable by a device such as a balloon. In the preferred embodiment described below, the adapter stent of the present invention is provided as a tubular structure consisting of a liquid-impermeable outer structure with an inner space to enclose a liquid or gel material substance during prolongation. In this way, all blood flow will be directed through the interior of the adapter holder in which the replacement valve is positioned.

In one aspect of the invention, a method of placing a valve in a tubular organ having a diameter greater than the diameter of the valve is provided. The method includes delivering an expandable tubular adapter to a desired location within the tubular organ, wherein the adapter includes an enclosed volume surrounded by an outer cylindrical wall having a first diameter, the outer cylindrical wall and an inner cylindrical wall having a second diameter less than the first diameter Concentrically spaced, first and second end walls extend respectively at the proximal and distal ends of the adapter between the outer cylindrical wall and the inner cylindrical wall. The method also includes expanding the outer cylindrical wall relative to the inner cylindrical wall such that the outer cylindrical wall contacts the tubular organ, and placing the valve within the inner cylindrical wall of the adapter. The method also includes placing a material within the enclosed volume of the adapter to expand the outer wall relative to the inner wall, the material may include, for example, a liquid or gel and may be a fully or partially hardened material. Alternatively, the valve may be positioned within the cylindrical inner wall before the adapter is delivered to the desired site.

In another aspect of the invention, an apparatus for placing a valve in a tubular organ having a diameter greater than the diameter of the valve is provided. The device includes an enclosed volume surrounded by a cylindrical outer wall having a first diameter spaced concentrically from a cylindrical inner wall having a second diameter smaller than the first diameter, and a first end wall and a second end wall respectively extending at the proximal and distal ends of the adapter between the outer cylindrical wall and the inner cylindrical wall. The device also includes a quantity of material contained within the enclosed volume and a valve mounted within the cylindrical inner wall of the adapter. The outer wall, the inner wall, or both can include at least one protrusion protruding from the surface to engage at least a portion of the valve.

Description of drawings

The present invention will now be further described with reference to the accompanying drawings, in which like structures are represented by like numerals throughout the several figures, and in which:

Figure 1 is a side view of an exemplary prior art adapter bracket;

Figure 2 is a schematic end view of the adapter holder shown in Figure 1 with a valved vein segment installed therein;

Figure 3 is a cross-sectional side view of a replacement valve of the type shown in Figure 1 implanted in the right ventricular outflow tract;

Figure 4 is a perspective view of an embodiment of an adapter bracket according to the present invention;

Figure 5 is a cross-sectional side view of the adapter bracket shown in Figure 4;

Figure 6 is a side view of a stented valved vein segment as described in the Tower et al. and Bonhoeffer et al. references cited above;

Figure 7 is a side view of a delivery system with a valve segment according to the present invention;

Figure 8 is a side view of the valved vein segment shown in Figure 6 delivered by the system shown in Figure 7;

Figure 9 is a cross-sectional side view of a replacement valve positioned within an adapter stent of the present invention implanted in the right ventricular outflow tract;

Figure 10 is a side view of a delivery system for an adapter stent according to the present invention;

11 is a partial cross-sectional view of another embodiment of an adapter bracket including beams or protrusions extending outwardly from an outer surface of the adapter bracket;

Figure 12 is a partial cross-sectional view of another embodiment of an adapter bracket including beams or protrusions extending inwardly toward an open channel in the adapter bracket;

Figure 13 is a cross-sectional view of another embodiment of an adapter stent including a valve segment therein according to the present invention;

Figure 14 is a schematic perspective view of a valve attached to a stent according to another embodiment of the present invention;

15 is a cross-sectional side view of another embodiment of an adapter stent of the present invention comprising the valve and stent shown in FIG. 14 in a first position; and

16 is a cross-sectional side view of the adapter stent shown in FIG. 15 including the valve and stent shown in FIG. 14 in a second position.

Detailed ways

Referring now to the drawings, in which like parts are numbered the same, and initially to FIGS. 4 and 5, there is shown an exemplary construction of an adapter bracket 200 in accordance with the present invention. Adapter stent 200 may be used to reduce the infundibulum or right ventricular outflow tract to a diameter suitable for a percutaneous pulmonary valve. That is, the adapter stent 200 provides an area of the appropriate size or diameter to accept valve placement, such as in areas where the infundibulum or right ventricular outflow tract is too large to accommodate the valve. Adapter stent 200 includes a substantially cylindrical balloon 202 surrounding an inner channel 204 extending substantially through its center. The inner channel 204 defined by the inner wall 206 of the balloon 202 is positioned substantially concentrically with respect to the outer surface 208 of the balloon 202, although possibly at least slightly offset. End walls 210 and 212 extend between inner wall 206 and outer surface 208 to provide balloon 202 with a closed tubular structure. End walls 210 and 212 may be substantially straight or flat and extend in a substantially vertical direction from one or both of inner wall 206 and outer surface 208 toward the other of inner walls 206 and 208 . Alternatively, end walls 210 and 212 may also be substantially concave or convex portions of the balloon that provide a smooth transition surface between inner wall 206 and outer surface 208 .

As described further below, balloon 202 may be placed into a patient in a substantially deflated or collapsed state and thereafter sequentially filled with one or more of a variety of substances. For example, these substances may be of a non-hardening type such as air or liquids of different viscosities. In this case, the balloon may be provided with a mechanism, such as a plug or other closure mechanism, to retain the material contained within the balloon (ie avoid leakage). It is also conceivable that the balloon itself is constructed of a self-sealing type of material that can be perforated or otherwise broken to allow filling of the balloon through a nozzle or other device, and which will self-contain after the balloon filling device is removed. Seal again. Alternatively, the balloon may be filled with a compound that may be fully or partially hardened such that the compound cannot leak or transfer from the balloon once hardened. The hardenable material may harden rapidly or instantaneously therein after it is injected or placed within the balloon, or the material may gradually harden over a period of time, such as in response to the temperature of surrounding body fluids and tissues. Other exemplary materials that may be used within the balloon include the following: saline, collagen, silicone, hydrogel, blood, foam, beads or spheres made of glass, polymers or metals, and the like.

While the balloon and/or adapter holder have been described above as being substantially cylindrical in shape, it will be appreciated that the balloon may also be shaped in a variety of ways within the scope of the present invention. For example, a balloon may have an outer wall, eg, substantially oval, oval, spherical, or irregularly shaped, and the inner wall of the balloon may be the same or different in shape than the outer wall. In either case, the inner wall is configured to receive the valve and the outer wall is configured to securely contact a body opening into which it is inserted for a sufficiently large portion of its area. That is, the outer wall of the balloon may have various irregularly shaped contours, eg, necessary to accommodate congenital irregularities of the right ventricular outflow tract. In this regard, the balloon and/or adapter stent may have an outer wall that is substantially cylindrical when in a folded or semi-folded state, but which is relatively conformal such that its outer wall is opposite when expanded within a suitable body opening. irregular. Accordingly, the adapter stent of the present invention can be used in areas of the body that do not include regularly shaped tubular openings. Additionally, as with any balloon and/or adapter scaffold, the inner channel may be slightly or significantly offset (ie, not concentric) relative to the outer surface of the balloon.

Balloon 202 may be made of any material that is compatible with its contents and is preferably impermeable to body fluids. In any of the embodiments of the invention, the balloon may be formed from one or more materials that form a continuous conduit that maintains the balloon's expanded state for an extended period of time. That is, once the balloon has been sealed, materials placed within the interior region of the balloon should not transfer or leak, and fluid outside the balloon should not migrate into the interior region of the balloon. In other words, the material from which the balloon is made should be impermeable to any fluids it contacts. Exemplary balloon materials include PTFE (polytetrafluoroethylene) or ePTFE (expanded polytetrafluoroethylene), although a wide range of impermeable materials or combinations of materials may also be used. It is also contemplated that the balloon surface may include materials that facilitate tissue ingrowth or pannus, such as fabrics or other materials with biocompatible and biostable coatings and/or that facilitate balloon repair in place. surface structure. This material may make up the entire balloon, or only a portion of the balloon may include material that facilitates tissue ingrowth.

In one configuration of the invention, the material making up balloon 202 is sufficiently flexible to conform to a variety of tissues so that a particular size and shape of adapter holder 200 can be configured for use in a variety of patients. Additionally, the balloon 202 is desirably designed to provide the inner passage 204 with a predetermined size when inflated regardless of the distance between the inner wall 206 and the outer surface 208 . That is, if balloon 202 is to expand to fit abnormally large tissue, inner channel 204 may maintain a predetermined diameter to accept the valve in its proper orientation. Accordingly, balloon 202 may be constructed of a single material or of combinations of materials, portions, and/or components that vary in thickness or other properties within specific regions of the balloon to allow for a desired expansion profile. For example, the portion of balloon 202 that makes up inner wall 206 may be relatively non-deformable or non-expandable compared to the portion of balloon that makes up outer surface 208, such that adding material to the interior region of balloon 202 will not allow balloon 202 to expand into the inner passageway. 204 while only allowing the outer surface 208 of the balloon 202 to expand away from the inner wall 206 . In this way, the diameter of the inner channel 204 can be maintained to accept the specific size of the replacement valve. Additionally, the distance between end wall 210 and end wall 212 is preferably approximately equal when balloon 202 is collapsed or when balloon 202 is partially or fully expanded. However, the length of balloon 202 may also increase at least slightly as material is placed therein.

Expansion of the balloon of the present invention may involve actual stretching or expansion of the material from which the balloon is made in response to adding material to the internal volume of the balloon. In other embodiments, however, the material itself does not actually expand or stretch, and filling of the interior volume of the balloon causes the walls of the balloon to move away from each other, thereby expanding the interior balloon volume.

Balloon 202 may be covered or partially covered with one or more substances to control or prevent valve ingrowth and seal, such as Dacron, PTFE, tissue, and the like. The material from which the balloon is made can include a material that is substantially void-free on first use but allows limited leakage short-term prior to implantation. This type of material becomes impermeable when implanted. Metal scaffold materials may also be used in combination with balloon materials to allow for tailored radial forces of the balloon 202 . Additionally, the balloon may include, for example, loops, barbs, hooks, teeth, or other protrusions or indentations that protrude or protrude into the inner balloon material, the outer balloon material, or both. An example of this structure is shown in adapter bracket 250 shown in FIG. 11 . Adapter stent 250 includes a substantially cylindrical balloon 252 surrounding an inner channel 254 extending substantially through the center of substantially cylindrical balloon 252 . Balloon 252 includes an inner wall 256 that defines an inner channel 254, wherein inner channel 254 has a substantially constant diameter over its length. Balloon 252 also includes an outer wall 258 spaced from inner wall 256 . Extending outwardly from outer wall 258 is at least one protrusion 260 which may serve as, for example, a discrete bump or bump, or may comprise a beam extending around all or a portion of the outer perimeter of balloon 252 . The protrusions 260 may be spaced apart from each other, as shown, or may be a continuous textured surface of the outer wall 258 . Another alternative configuration for protrusion 260 includes one or more swing beams extending continuously or semi-continuously along the length of balloon 252 .

The number, spacing and specific configuration of any protrusions 260 extending from the outer wall 258 are selected to provide and/or facilitate specific features of the adapter holder with respect to specific procedures. That is, these protrusions may be provided, for example, to increase the radial force of balloon 252, reduce the risk of its migration, and/or enhance the overall structural integrity of the adapter stent. Any protrusions 260 provided may be integrally formed with the outer wall 258 or may be adhered or otherwise attached to the balloon 252 using the same or a different material from which the balloon is made. An example of such an alternative protrusion is a plug that extends into and out of the outer wall 258, such as the type commercially available from AGA Pharmaceuticals, Golden Valley, Minnesota, under the name "Amp". Lazi (AMPLATZER) vascular plug "self-expanding cylindrical mesh device.

FIG. 12 shows a portion of another embodiment of an adapter stent 270 including a balloon 272 surrounding an inner channel 274 extending substantially through the center of the balloon 272 . Balloon 272 includes an outer wall 276 spaced from an inner wall 278 defining an inner passage 274 . The outer wall 276 has a substantially constant diameter throughout its length; however, the inner wall 278 includes at least one protrusion 280 that projects into the inner passage 274 . The protrusion 280 may comprise any variation described or contemplated above with respect to the protrusion extending from the outer wall 258 of the adapter bracket 250, as desired. One function of this protrusion 280 is to control the position of the new valve within the adapter stent, eg to avoid valve migration. That is, the protrusions aid in introducing, positioning and/or securing the valve within the adapter holder. Alternatively, a single adapter bracket may use a combination of protrusions protruding from its inner and outer walls and along all or part of the wall length.

Figure 13 illustrates yet another embodiment of an adapter stent 300, further including a valve segment 302 positioned therein. Adapter stent 300 includes a balloon 304 surrounding a substantially cylindrical inner channel 306 . Inner channel 306 includes at least one curved portion 308, thereby varying the diameter of inner channel 306 along a portion of its length. In one embodiment, discrete curved portions 308 are provided to correspond to the leaflets of the particular valve to be used therein. That is, if a tri-leaflet valve is to be used, three corresponding curved or spherical portions 308 may be provided. Accordingly, curved portion 308 may correspond to the anatomical or natural shape of the valve to be implanted. However, curved portion 308 may also be continuous around all or part of the inner boundary of balloon 304 . Such curved portions may alternatively or additionally be provided on the outer wall of the adapter holder to conform to the patient's anatomy.

FIG. 6 shows another example of a stented valve vein segment 50 that has been developed that may be positioned within an adapter stent such as adapter stent 200 that was previously implanted. The stented vein segment 50 may correspond to that described in the above-cited Tower et al. and Bonhoeffer et al. references and essentially includes a stent 52 and a vein segment 54 . The outer diameter of the stented vein segment 50 is expandable to be as large as the diameter of the inner channel 204 of the adapter stent 202 . Stent 52 may be made of platinum, stainless steel, or other biocompatible metal. Although fabricated using wire as described in the above-cited Tower et al. application, it can also be fabricated by machining metal tubes into stents. The vein segment 54 is installed in the bracket 52 , and the valve included in the vein segment 54 is located between two ends of the bracket and fixed to the bracket by a suture 56 . Stitches 56 are located at the proximal and distal ends of the stent, and preferably at all or nearly all intersections of the stent, as shown. A more detailed description of the fabrication of stented vein segments is found in assignee's co-pending U.S. Patent Application, "Heart Valve Therapy Devices and Methods of Making the Same.

FIG. 7 shows a system for delivering a valved vein segment of the type shown in FIG. Delivery system 60 includes a housing 62 covering an inner balloon catheter (not visible in the figure). The housing includes an expanded distal portion 64 into which the stented valved vein segment is positioned. The venous segment is compressed around a single or double balloon on the inner catheter. A tapering tip 66 is mounted on the distal end of the inner catheter to facilitate passage of the delivery system through the patient's vasculature. The system also includes a guide wire 68 that can be used to guide the delivery system to its desired implantation site.

The delivery system of FIG. 7 and its use may be the same as described in the above-cited Tower et al. application, except that the vein segment is placed within the middle of an adapter stent pre-placed, such as adapter stent 200, rather than expanded against a malfunctioning native or prosthetic valve. . The delivery system can be advanced using guidewire 68 to the desired valve implantation site, after which housing 62 is retracted to allow balloon inflation of the venous segment, as shown in Figure 8, as described below.

FIG. 8 shows the mechanism of expanding a stented valved vein segment such as vein segment 50 within the middle of a pre-implanted adapter stent such as adapter stent 200 . Housing 62 moves proximally, exposing balloon 72 mounted on inner catheter 70 . The balloon 72 expands, thereby expanding the vein segment 50 against the inner surface of the pre-implanted adapter stent, stabilizing and sealing the vein segment within the adapter stent. If a protrusion or other lead-in feature is provided within the adapter holder, the vein segment 50 can engage with that feature. The balloon is then deflated and the delivery system is retracted proximally.

Figure 9 is a schematic cross-sectional view of a replacement valve implanted in the right ventricular outflow tract 40 within the adapter stent 200 of the present invention. As noted above, the replacement valve may be implanted in adapter stent 200 at the same time the adapter stent is implanted in the patient, or the replacement valve may be implanted some time after adapter stent 200 is implanted. As shown, the outer surface 208 of the adapter bracket 200 expands against the inner wall of the outflow channel 40 . As noted above, the inner channel 204 is preferably maintained at a specific diameter suitable for securing and maintaining the replacement valve. Thus, depending on the size of the spout 40 , the outer surface 208 may be relatively close to the inner channel 204 or spaced farther from the inner channel 204 . In other words, if the outflow is larger, the outer surface 208 will be spaced farther from the inner channel 204 than if the outflow is not large.

The outer surface 208 of the adapter bracket 200 preferably contacts the inner surface of the spout 40 throughout its entire length, although portions of the outer surface 208 may not contact the spout. In any event, sufficient outer surface 208 should be in contact with outflow tract 40 to complete the seal and prevent its migration after implantation. The adapter stent is shown mounted downstream of the native valve leaflets 42 to allow continued operation during the implantation of the adapter stent 200 and stented vein segment 50 . Optionally, vein segment 50 may be placed within adapter stent 200 within a few weeks of its initial implantation. In this figure, the leaflets 58 of the vein segment 54 are also shown within the adapter holder 200 .

Figure 10 illustrates an exemplary system that may be used to deliver an adapter stent according to the present invention, somewhat similar to the system used to deliver venous segments. The delivery system 21 comprises a housing 22 covering an inner catheter (not visible in the figures). Housing 22 has an expanded distal portion 24 into which adapter stent 200 (with or without a valved vein segment) may be placed. Adapter stent 200 may initially be in a collapsed state, compressed around the inner catheter and held in its compressed configuration by housing 22 . Reduction tip 26 is mounted on the distal end of the inner catheter and is used to facilitate passage of delivery system 20 through the vasculature. The system also includes a guide wire 28 that can be used to guide the delivery system 20 to its desired implantation site.

The delivery system 21 also includes a mechanism 32 in communication with the adapter stent to expand or expand at the desired implantation site. Mechanism 32 can include various devices that can provide desired materials to the interior of adapter holder 200, such as a pump that can move a fluid or gel into adapter holder 200, a source of compressed air or other gas that can be controlled to expand adapter holder 200 by a predetermined amount. wait. That is, the material used within adapter stent 200 will determine the type of mechanism 32 used to expand or expand. Optionally, delivery system 21 and/or adapter stent 200 may be provided with a sealing mechanism (not shown) to seal or close any openings in adapter stent 200 after material is injected or placed therein to keep material from leaking from stent 200 .

Housing 22 can be moved proximally by mechanism 32 in response to expansion of adapter stent 200, or by pulling housing 22 from one end, thereby allowing adapter stent 200 to expand away from inner catheter 30, as shown in the device configuration. The distal segment of the adapter stent 200 can engage the vessel wall at the desired implantation location, thereby stabilizing the stent. Housing 22 is then moved further proximally, releasing the proximal segment of the adapter stent, after which the adapter stent is free to expand in its diameter until it contacts the vessel wall. Material can continue to be added to the adapter stent 200 until it expands or expands to the desired size. The delivery system is then retracted proximally. In certain configurations, the valved vein segment is pre-installed within the adapter stent 200 such that inflation or expansion of the adapter stent 200 with the valved vein segment installed therein completes the implantation of the replacement valve. Alternatively, the valved vein segment can be placed into the adapter holder at a later time.

The stented valved vein segment described and shown for the adapter stent of the present invention is compressible for installation in a patient and expandable, for example, by the balloon portion of the delivery system. However, it should also be understood that other types of stented valves may also be used, such as the type known as self-expanding. The self-expanding stent is compressible to fit within a patient, and then easily expanded to a desired size by removing the specific external force used to maintain the stent in a compressed state. Other types of stented valves that can be compressed and expanded in ways other than those described herein can also be used, as long as the valve can be placed within an adapter stent in a patient.

Referring again to FIG. 13 , the valve segment 302 has been preattached or preinstalled in the inner channel 306 of the balloon 304 so that the implantation procedure can be accomplished in a single step. That is, rather than installing the adapter stent first and then installing the valve segment in the inner channel, Figure 13 shows an adapter stent assembly that allows the surgeon to dispense with the use of a delivery system with a balloon to expand the valve segment. The illustrated valve segment 302 is substantially in the form of a bovine jugular vein including a spherical region 310 expandable into the curved portion 308 of the balloon 304 . This configuration may provide less stress on the leaflets 312 as the spherical region 310 is not compressed or deformed into the inner channel 306 of the balloon 304, but allows for its autoatomic form to be substantially maintained.

14 shows an embodiment of a valve 320 (shown in phantom for clarity) attached to a stent 322 according to another embodiment of the invention, wherein the valve 320 includes leaflets 324, and the stent includes a proximal end 328 and an opposite distal end. End 326. The proximal end 328 may at least partially cover, for example, tissue during a procedure of securing the stent 322 to the valve 320, such as by a suturing operation. Stent 322 may comprise a braided or wire mesh material, or any other suitable stent material. 15 shows the valve-stent assembly shown in FIG. 14 positioned within an adapter stent or balloon 330 with the leaflet 324 substantially within the inner channel 332 of the balloon 330 and with the proximal end 328 of the stent 322 protruding from the balloon 330. one end. Stent 322 is attached to balloon 330 , such as by suturing proximal end 328 of stent 322 to balloon 330 around at least a portion of the circumference of stent 322 to balloon 330 . Balloon 330 may be provided with a cuff or other extension (not shown) to attach the stent without compromising the strength of the balloon. At this point, the adapter stent with the stented valve installed therein can be shipped, for example, to a clinic.

Optionally, the valve-stent assembly shown in FIG. 14 can be inverted into the configuration shown in FIG. 16 by pulling the distal end 326 of the stent 322 through the inner channel 332 of the balloon 330 until substantially everted as compared to FIG. 15 . Thus, since the volume of material in this region during the compression procedure is less than the volume of material that the stented valve will hold within inner channel 332, the balloon with the stented valve attached can be compressed to a smaller size for delivery of the system into the patient. Thereafter, the adapter stent can be used in the same manner as described with respect to other embodiments of the invention, such as including expanding the balloon with material, removing the delivery device, etc., but also by pressing the distal end 326 of the stent 322 back into the inner channel 332. The steps of the insertion process described above are reversed so that it can be used as a valve for the patient.

Finally, while the invention described above is particularly applicable to replacing valves in the right ventricular outflow tract, the invention may be used to replace valves in other blood vessels or other tubular organs. Also, while bovine jugular vein is disclosed as a source of valved segments for use in the practice of the present invention, other sources of animals or sources of blood vessels may be substituted. Likewise, polymeric or thin metal valves can also be used. Additionally, alternative exemplary replacement valves of the type described in the aforementioned US Patent Nos. 6,719,789 and 5,480,424 to Cox may also be used. Also, the above descriptions should be considered as illustrative and not restrictive.

The invention has been described with reference to several embodiments. Any patents, patent applications, publications and journal articles cited herein are hereby incorporated by reference in their entirety. The foregoing detailed description and examples have been given for clarity of understanding only. No unnecessary limitations should be understood therein. It will be apparent to those skilled in the art that many changes can be made to the described embodiments without departing from the scope of the invention. Thus, the scope of the present invention should not be limited to the structures described herein, but only by structures described by the language of the claims and the equivalents thereof.

Claims (8)

1. One kind be used to place valve in diameter greater than the equipment in the pipe of this valve diameter, this equipment comprises:

   Adapter; Said adapter comprise by the cylindrical outer wall with first diameter around enclosed volume; This cylindrical outer wall and concentric the separating of cylinder shape inner wall that has less than second diameter of said first diameter; First end wall and second end wall extend the near-end and the far-end of the said adapter between said cylindrical outer wall and the said cylinder shape inner wall respectively, and stretch out on the surface of at least one from said cylindrical outer wall and said cylinder shape inner wall of at least one integrally formed convexity;

   A certain amount of material that comprises in the said enclosed volume;

   Be installed on the interior valve of cylinder shape inner wall of said adapter.
2. 2. equipment as claimed in claim 1, wherein cylindrical outer wall and cylinder shape inner wall and extend said cylindrical outer wall and said cylinder shape inner wall between said first end wall and said second end wall comprise anti-liquid material.
3. 3. equipment as claimed in claim 1, contained material is a fluent material in the wherein said enclosed volume.
4. 4. equipment as claimed in claim 1, contained material is a gel rubber material in the wherein said enclosed volume.
5. 5. equipment as claimed in claim 1, contained material is at least semisolid in the wherein said enclosed volume.
6. 6. equipment as claimed in claim 1, wherein said cylindrical outer wall comprise at least one convexity that is away from the central longitudinal axis of said equipment from this cylindrical outer wall surface and stretches out.
7. 7. equipment as claimed in claim 1, wherein said cylinder shape inner wall comprise from this cylindrical inner wall surfaces towards the central longitudinal axis of said equipment and at least one convexity of stretching out.
8. 8. equipment as claimed in claim 7, wherein said at least one integrally formed convexity comprises a plurality of convexity spaced apart from each other.

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